"...a script to automate some process checking ... to check processes...start it."

This is the classic task for Nagios.

See Eventhandlers for details.

The bash example provided at the same place can be easily ported to Perl.

For a fork of Nagios with a more modern GUI and a lot of other useful features please see Re: perl module help.

But please note: The setup of the "old" Nagios is much easier.

Regards, Karl